Background.- Acute appendicitis is a common surgical problem. Aim of the Study: To assess Alvarado score as an admission criterion for adult patients with suspected appendicitis in order to decrease unnecessary admissions to surgical wards. Patients and Methods: A prospective study of consecutive patients attending the Emergency Department (ED) of Riyadh Medical Complex with suspected appendicitis. The patients were managed according to the algorithm of the study protocol and discharged after clinical improvement either from ED or from the ward. They were followed by telephone 2-3 days later. Alvarado score was obtained in the ED in all patients. Results: The study included 211 patients, 60 patients were observed in ED and discharged, 151 patients were admitted and 137 of them were operated with a negative rate of 12.5%. The remaining 14 patients were observed and discharged. No patients with a score of 4 or less had appendicitis. Conclusion: Though the diagnosis of acute appendicitis remains mainly clinical, Alvarado score can be recommended as a helpful tool for the admission criteria and further management in order to reduce unnecessary admissions and to reduce the morbidity and mortality of acute appendicitis

Acute appendicitis is one of the commonest surgical emergencies. Simple appendicitis can progress to perforation, which is associated with a much higher morbidity and mortality. Concern regarding delay in diagnosis has increased because most of the patients are not seen initially by surgeon. The Alvarado score was first described in 1988 by Alfredo Alvarado as a practical score for the early diagnosis of acute appendicitis, that can be instituted easily in the outpatient setting[1]. It is a 10­point scoring system based on clinical symptoms, signs and differential leukocyte count [Table - 1]. We designed this study with the aim of assessing whether Alvarado score can be used in the decision of admission or discharge of patients above 12 years of age presented with suspected appendicitis to the ED.

Patients and Methods

This is a prospective study comprising consecutive patients who attended the ED of Riyadh Medical Complex with suspected appendicitis during a 2-month period from the 1 st of March through 30 th April 2003. All adult patients with suspected acute appendicitis were included in the study. Most of the patients came directly to the ED although some patients were referred from primary health centers with suspected appendicitis. They were seen by specialist surgeon in the ED. The management protocol is depicted in [Figure - 1]. Patients were assessed in the ED, and Alvarado score was obtained for all patients within 48 hours from the onset of the symptoms and the majority within 24 hours. Patients with equivocal signs and symptoms were observed in the ED for up to 6 hours, and discharged after clinical improvement. They were told to return to the ED if their symptoms relapse or worsen. They were contacted on telephone 2-3 days later for follow up. Patients who did not improve after observation in the ED or presented with clear features of acute appendicitis were admitted to the surgical ward. If patients were thought on clinical reevaluation to require appendicectomy, then this was performed, regardless of the score. Whether patients were discharged, observed or admitted, Alvarado score was compared with the final result [Table - 2].

Results

The study included 211 patients comprising 125 males (59%) and 86 females (41%) with ages ranging from 13 to 70 years (mean 32yrs). A total of 151 patients (72%) were admitted to the hospital, 137 of them (91%) were operated with intention to treat appendicitis, but 17 patients did not have appendicitis with negative rate of 12.5%. Fourteen patients (9%) of the admitted patients were kept under observation. All of them except one were discharged after clinical improvement. One patient who failed to improve was operated and found to have acutely inflamed appendix. All inflamed appendices were confirmed operatively and by histological examination. Sixty patients (28%) were discharged from ED after observation for 2­6 hours and interviewed by telephone 2-3 days after discharge from ED. All of them improved except one who was operated in another hospital for appendicitis and his score on discharge from the ED was 7 [Table - 2]. Three female patients were pregnant; two of them with score of 4 and 6 were admitted, observed and improved within 24 hours, discharged and interviewed by telephone three days later. They were asymptomatic. One pregnant patient scoring 10 points was operated and found to have acutely inflamed appendix. Regarding the position of the appendix intra-operatively, 83 were retrocaceal, 11 pelvic and seven retroileal. In the other patients, the position of the appendix was not identified. No clear effects of the site of the appendix on the patient score were noted. No patients with gangrenous or perforated appendicitis scored less than 8. No patient with score of 4 or less was found to have appendicitis. Two female patients out of four with Alvarado score of 1-5 were found intraoperatively to have ruptured appendicitis. right ovarian cyst rather than acute

Discussion

The diagnosis of acute abdominal pain is still a major problem despite the considerable improvement in history taking, clinical examination, computer-aided decision support and special investigations such as ultrasound [2]. General practitioners and emergency physicians face difficult problem when presented with a patient of right iliac fossa pain with equivocal signs. The decision to admit or discharge these patients is not always straightforward. Appendicitis still poses diagnostic challenge and many methods have been investigated to try to reduce the removal of a normal appendix without increasing the perforation rate. Radiological methods such as ultrasonography, which is operator dependent and computed tomography with its expense and radiation hazard as well as laparoscopy, which is invasive and expensive, are all methods that have been investigated previously[3],[4],[5] . Ohmann in his prospective study of diagnostic scores for acute appendicitis concluded that scoring systems seem to be ideal for supporting the diagnosis of acute appendicitis because they are accurate, non-invasive, and require no special equipment[6] . Chan et al in a previous study found that patient with low Alvarado score (less than 5) did not have appendicitis[7] . Owen et al (1992) reported that there was no perforated appendicitis in patient with a score of less than 6, and suggested the use of the score by general practitioners[8].

Our results showed that no patient with a score of 4 or less had appendicitis. We discharged 37 patients in this score range and none of them had appendicitis. In addition, four patients were admitted with this score range observed and discharged after clinical improvement and none of them had appendicitis and three patients in the same score admitted, operated and found to have negative appendicitis. The score of 5 or more can be used as a criterion for referral and admission of patient with suspected appendicitis especially for general practitioner and emergency physician. The same result was concluded in prospective study done by Chan. He incorporated Alvarado score in an algorithm for patient admission for suspected acute appendicitis[9] .

Assessing the sensitivity and specificity of Alvarado score as a defining line for admission of adult patients with suspected appendicitis, we have found that a score of 4 has the sensitivity of 100% (no patient with acute appendicitis has been missed) and specificity of 49.4%, whereas if we use a score of 3 as a defining line the sensitivity is 100% but with a low specificity (30%), which will increase the unnecessary admission. Use of a higher score (score of 5), the sensitivity will be 98.3% (possibility of missing patients with acute appendicitis), and the specificity will be 69.6% [Table - 3]. In our study the Alvarado score worked well in men. However in women it had high false positive rate (23% of women with scores of 6 or more, did not have appendicitis while in men only 3%). The same result has been concluded in prospective study done by ReZa and Mitra in 1997[10][Table - 4]. Good clinical assessment and skills of the surgeon remains the mainstay of establishing the diagnosis of acute appendicitis[11],[12].